Yeah, let go. You will gain nothing from beating yourself up over anything. Look at the good things, let go the icky. It's a nice, romantic thing you did with the ring, and I'm sure that made her happy.
I cry at the drop of a hat, but usually that is connected to my thought processes and not my emotions. I might be a little like your wife regarding emotions in that many times people in my life get this idea that I am not reacting or feeling as much as I "should" in a situation. My ex-husband used to get so upset because he thought I wasn't "sentimental enough." But I grew up in a household where self-preservation meant keeping my feelings under wraps, especially when the shit was hitting the fan. I usually liken how I handle stress to a duck. We see a duck on a lake and it looks like it's just sitting there, floating on the water -- BUT under the surface, its little webbed feet are all go-go-go. So, imagine how it feels for someone to seem reserved on the outside while processing a lot of stuff on the inside.
I also wanted to say that, for lots of newly poly people, it helps to have some transition time between being with one lover in their environment and coming back to a partner in their own home environment. It can be hard, and weird, to jump right into day-to-day life and relating. Some people need an hour or two, some a day or two, to process before reconnecting with their SO. There is a thread that started to address that here: How do you avoid distraction?
Most important, though, is to stop beating yourself up. Now.